CTIA Recommends MicroUSB, 3.5mm Mini Plugs For Phones

Washington — CTIA-The Wireless Association is encouraging further standardization of inputs and outputs on cellular phones, following up on its previously announced support for the industry's Universal Charging Solution (UCS) for cellphone chargers.

“The adoption of common interfaces for input/output features extends the consumer-friendly and environmentally focused universal charger solution that the wireless industry announced in April 2009,” CTIA said. The recommendations, which are voluntary, will also simplify life for consumers and retail stores, which could stock fewer accessory SKUs, CTIA general counsel Michael Altschul told TWICE.

In its recommendations, the association called on handset makers to adopt MicroUSB for data transfer to PCs and other devices. For attaching hands-free and stereo headsets, the association recommended the use of MicroUSB or a 3.5mm mini plug. The UCS solution is also MicroUSB-based, requiring chargers connect to cellphones via MicroUSB connection.

The recommendations don't preclude handset makers from using Wi-Fi or Bluetooth for data and audio functions, Altschul noted.

Though MicroUSB supports data transfer, the CTIA is not including HD video in its voluntary commitment, Altschul said. “There was uncertainty over whether MicroUSB throughput would be sufficient to support HD video, so our voluntary commitment doesn't extend to HD Video.” The CTIA will “revisit” the HD video question as technologies develops further, he said.

Under CTIA's initiative, handset makers supporting the voluntary standards would:

• use the USB Micro-B receptacle for charging and data transfer and the 3.5mm mini plug for audio input/output for the use of ear buds/headphones and microphones.
• use the USB Micro-AB receptacle for charging and data transfer and the 3.5 mm mini plug for audio input/output.
• use the USB Micro-AB receptacle for charging, data transfer and acting as a host to USB digital headsets.

Micro-B and Micro-AB receptacles connect to any PC, laptop or USB dongle, Altschul said.

Apple was a participant in the working group that developed the recommendations, and “Apple voted for it,” Altschul noted, but the CTIA executive said he isn't privy to any plans by Apple to incorporate MicroUSB in future products. Apple's iPhone uses a proprietary multi-pin connector for tethered data transfers as well as for docking the phone with iPod/iPhone tabletop music systems.

Apple did not respond to an inquiry about its MicroUSB plans, if any.